How to unblock a toilet: 6 different ways to unclog it

You can unblock a blocked toilet with a plunger, or hot water, caustic soda, rubber gloves, a coat hanger, or the toilet brush, depending on the type and location of the blockage. In this article, we’ll tell you how to unblock a toilet if the water won’t go down the pan.

In 2016, the drain unblocking organisation Welsh Water told the BBC that the drain network is being used as a bin. In fact, the UK spends tens of millions of pounds on drain unblocking services every year. Hopefully, you won’t add to that statistic – here’s how to unclog a toilet, without – fingers crossed – having to get an emergency plumber.

How to unblock a toilet – flushing overview

When you flush the toilet, water flows from the cistern into the pan. The pan contains a bend or trap, which keeps a small body of water present. This acts as a barrier between your bathroom and the sewer, keeping bad smells from the drain out of your house. The shape of the trap also creates a siphon effect, helping to suck the effluent out of the pan. Most toilet blockages are located inside the pan, i.e., the porcelain component.

Tips and equipment

There are a few things to think about before beginning this job, which will hopefully make it as bearable as possible.

  • Rubber gloves – These are pretty much the cardinal piece of equipment for this task. Plus, if you know what it is that’s blocking your toilet, such a nappy or toy, you can use them to simply reach in and grab it.
  • Ventilation – Make sure the area is well ventilated. Open the bathroom window to let plenty of fresh air in. Don’t forget, however, to close certain doors. Bad smells will travel throughout the house.
  • Old newspaper or towels – Newspaper is a cheap way of soaking up any accidental spills. It can be disposed of easily, but don’t throw it down the toilet! Towels can be used as something more robust, but you may wish to throw them away afterwards.
  • Old clothes – Depending on the severity of the blockage, you may want to don some clothes which you don’t mind getting dirty.
  • Hot water – Some of these strategies involve the use of hot water, so be careful not to scald yourself.
  • Chemicals – Some of these strategies involve the use of chemicals. Always read the label, and never mix chemicals. This could result in a dangerous chemical reaction.

Before you begin, don’t keep flushing, especially if the pan is full to the brim and there’s no sign of it disappearing. You may end up with very wet feet and a lot of regret!

How to unblock a toilet with a plunger

In order to unblock a toilet with a plunger, you’ll need one specifically designed for this purpose. Toilet plungers have an extension on the cup which ensures they form a good seal in the pan. A plunger without this cup – known as a sink plunger or a cup plunger – is intended for unblocking sinks, showers, and baths.


  1. Make sure there’s water in the pan. For argument’s sake, we’ll assume that there is. However, if the water has drained away very slowly, you’ll need to top it up again. Pour some water in but don’t flush it. This is to ensure that the plunger cup is covered and to prevent the ingestion of air.
  2. Place the plunger in the water. You should do this in such a way so that there as little air in the plunger as possible. That’s because you want to make sure the plunger is agitating the water. Any air inside will act as a cushion for the water and stop its movement from shifting the obstruction.
  3. Place the plunger over the hole. Make sure that it forms a seal over the hole. If this is difficult, try dousing the cup of the plunger in hot water. This should make it more malleable.
  4. Plunge carefully at first. Avoid the temptation to plunge as hard as you can at first. Any air inside the cup may cause a splash.
  5. Plunge! A combination of small, sharp plunges and forceful, vigorous ones should get the water moving and the blockage on its way out.
  6. Be patient. You may not get immediate results.

No plunger?

If you didn’t have any luck with a plunger, or you simply don’t have one, there are still loads of different ways to unblock your toilet. For starters, you can try it with the toilet brush. It won’t be as effective a good plunger, but it may be enough by itself to agitate the water enough to clear the blockage.

How to unblock a toilet with hot water

This method is best used when a toilet is partially blocked, as pouring water into a toilet that’s completely blocked will probably just make the pan overflow.

  1. Fill up a bucket with hot water from the sink or the bath. Never use boiling hot water from the kettle, as sudden changes in temperature can crack the porcelain.
  2. Pour the water into the pan. You’ll need to pour the water as hard as you can without making the pan overflow. The higher the point from which you can do this, the better. In theory, the force of the large volume of water should shift the obstruction. The warmth of the water may also help to loosen any fats that are causing the blockage.

How to unblock a toilet with a mop

You can use a mop and plastic bag in order to unblock a toilet. This method works roughly the same way as a plunger, by agitating the water. You should ideally have three or four carrier bags to do this method as cleanly as possible.

  1. Place a carrier bag over the mop head. Use the handles of the bag to tie it in place; alternatively, hold it in place with your other hand.
  2. Place the mop and bag in the water.
  3. Use sharp, brisk strokes to push water down the hole. The movement of water should move the blockage. Once again, be patient – it may take a dozen or two strokes before you get results. Don’t do it so hard that the bag breaks – you don’t want to be adding to the blockage.
  4. Let the bag drain. Once you’ve unblocked the toilet, let the bag drain. Most carrier bags, such as the ones you get in supermarkets, tend to have one or two small holes in the bottom. The bag will probably have filled up with some of the contents of the toilet.
  5. Dispose of the bag. Once it has drained, you can place one or two more carrier bags over it in order to take it off the mop head as hygienically as possible.
  6. Disinfect the mop.

How to unblock a toilet with caustic soda

Otherwise known by its chemical name of sodium hydroxide, caustic soda can be an extremely effective toilet unblocker. It is the active ingredient in many sink and drain unblockers, and is cheaply available from local DIY stores. It works using a combination of heat and chemistry. Mixing caustic soda water creates heat, which softens grease and fatty deposits. The caustic soda itself converts fat into glycerine and salts, which are water-soluble and can be flushed away. This method assumes that the pan is empty but the toilet is blocked (i.e. the water is draining away very slowly).


  1. Health and safety. Caustic soda can be exceedingly dangerous if not used correctly. When unblocking a toilet with caustic soda, you should wear chemical-resistant gloves and eye protection, and mouth/nose protection to stop you from inhaling the fumes. Make sure the area in which you are working is well ventilated.
  2. Prepare the mixture. Slowly add approximately 1 kg (2.2 lb) of caustic soda to approximately 4.5 litres (1 gallon) of water in a bucket. The mixture will bubble and fume. Keep your face away from the fumes, taking care not to inhale them. Tip: Always add caustic soda, never the other way round. Adding water to caustic soda will create an extremely high amount of heat. Never pour caustic soda crystals straight into the pan – the crystals will solidify and make the blockage worse.
  3. Slowly pour the mixture into the pan.
  4. Put the toilet seat down.
  5. Leave it overnight, or as long as stated by the instructions.
  6. The next morning, pour one or two buckets of hot water down the toilet. The toilet should now hopefully be unblocked.

How to unblock a toilet with a clothes hanger

It is possible to unblock a toilet with a clothes hanger/coat hanger. You can bend a basic metal clothes hanger into a suitable shape. However, you should be very careful not to scratch the porcelain of the pan.

  1. Bend the clothes hanger. Twist it out of its original shape until it is roughly straight. While leaving around a third of it to be used as a handle, bend the remaining two thirds into a curve which can be inserted into the hole. Bend the business end over itself in order to make it more rigid.
  2. Insert the wire into the hole. While following the shape of the bend, push your way forward to try to clear the path. Take care not to scratch the pan.


One of the most important things you can do to prevent a blocked toilet is to educate household members what shouldn’t go down the toilet, such as wet wipes, dental floss, tampons, and condoms. These things should be carefully disposed of with general household waste. They should never go down the toilet. Putting a basic bathroom bin next to the toilet should eliminate the temptation to flush these things. You should also make sure that younger family members know not to put random objects and toys in the loo.

There are certain chemicals, such a paint, which you should never flush down the toilet or even throw away in the household rubbish. Instead, you should take these to your local waste disposal facility. Some compounds, such as grease and wax, may solidify and create a blockage.

Take unwanted medicines and medical items to your pharmacist, GP or hospital. Dispose of used syringes and needles in a medical sharps box.

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